While there are thousands of types of fleas on the planet, only Ctenocephalides felis affects cats. However, that doesn't usually bring any comfort when you are dealing with a flea infestation on your feline friend. Fleas are an annoying problem for cats and their humans. But, beyond that, fleas can cause serious medical problems in cats.

Conditions Caused by Flea Infestation in Cats

Below are some ailments in cats that are caused by fleas:

Flea allergy dermatitis is a condition in which the cat is allergic to the saliva of fleas. When an allergic cat is bitten by fleas, her immune system over-reacts, resulting in excessive scratching with secondary hair loss, skin trauma, and infection. Learn more here: "Flea Allergy Dermatitis in Cats."

Flea bite anemia occurs when the cat loses more blood to the flea infestation than she can make to keep up. This condition can be life-threatening, especially in kittens, geriatric cats, or those that are debilitated from another disease process.

Tapeworm infection with Dipylidium caninum is a result of ingestion of an infected flea by the host cat. While tapeworm infections are not dangerous to cats, it is unsightly and bothersome to owners when tapeworm segments are passed rectally into the cat's bedding and other areas of the home. Sometimes cats will bite at their rear ends or scoot them across the floor if they have tapeworm segments dropping out. Learn more here: "Tapeworms in Cats."

Feline hemotropic mycoplasmosis is a serious illness that is transmitted by flea bites. The fleas transmit bacteria, either Mycoplasma haemominutum or Mycoplasma haemofelis to the cat. These organisms attach themselves to her red blood cells. The cat's body notices the bacteria and mounts an immune response, killing the affected red blood cells along with the parasites. This can lead to a serious anemia if the cat has a large infection. Death can occur if the condition is not properly diagnosed and treated with tetracycline antibiotics.

Bartonellosis is the infection of a cat with the bacteria Bartonella henselae. This infection is spread through flea bites. It is controversial how much the bacteria affects the cat itself. It may contribute to the painful gum disease stomatitis or other chronic inflammatory conditions, but this is not known with certainty. When a cat that is infected with Bartonella scratches herself and gets flea dirt in her claws, then scratches a human, the human may become infected. This results in the illness known as cat scratch fever, and it can be especially serious in immunocompromised people.

It is important to remember that cats do not always scratch themselves when they have fleas. Only cats that are allergic to fleas scratch when they are infested. Do not assume your cat doesn't have fleas, and thus isn't susceptible to the above conditions, because she isn't scratching herself. Take a look at this helpful article and video for tips on how to tell if your cat has fleas. Take a look at this helpful article and video for tips on how to tell if your cat has fleas.

Life Cycle of the Flea

Eggs: Eggs are laid on the cat by adult female fleas. These eggs then fall off of the cat into the environment, where they incubate. Within the home, this usually happens in the carpet, bedding, or furniture.

Larvae: Flea eggs hatch into small, crawling larvae. Larvae feed on the feces of adult fleas, which has also fallen off of the cat. The larvae molt three times. Then they spin a cocoon, becoming pupae.

Pupae: Inside the cocoon, the pupae develop into adult fleas. During this stage, fleas are very hard to kill. Pupae can remain dormant inside of the cocoon for up to one year. They do not emerge from their shelter until they sense a nearby host that can serve as a food source. They perceive this through vibrations, sound, light, and carbon dioxide variations.

Adult fleas: Adult fleas aggressively search for a host in order to ingest their first blood meal. Once she has eaten, the female flea will begin to lay eggs within two days, and she will lay eggs until she dies. The cycle begins anew from there. Fleas can live for 4 to 6 weeks after their first meal, but they are often groomed off by the host cat before then. Since a female flea can lay 40 to 50 eggs per day, a flea that is not killed or knocked off of the host can produce 2000 eggs in her lifetime.

Flea Control Products for Cats

There are many good options on the market today for flea control in cats. Below are the most common prescription products available at this time. It is not an exhaustive list.

It is extremely important that you never use a flea control product meant for a dog on your cat. Many of these contain permethrins, which are deadly if cats are exposed to them. Also be sure to always use the right product for your cat's age and weight.

Lufenuron is a chemical that controls fleas by sterilizing adult females so they can't reproduce and create a large flea problem in your home. This may not be sufficient for a flea allergic cat, as the product doesn't kill adult fleas. Products containing lufenuron include:

Program®: This product is available for cats as either a monthly oral tablet or liquid, to be given at home with food, or as an injection, to be given every six months by your veterinarian.

Imidacloprid is a medication that is very effective at killing adult fleas. It is available in the Advantage® line of products, as follows:

Advantage II® for Cats contains pyriproxifen in addition to imidacloprid. This allows the product to kill flea eggs and larvae as well as adult fleas. Fleas are killed on contact and do not have to bite the cat to be killed. It is a monthly topical formulation.

Advantage Multi® for Cats contains moxidectin in addition to imidacloprid. This allows it to act as a heartworm preventative, ear mite treatment, and adult flea killer. It also controls some intestinal parasites. It is a monthly topical formulation.

Seresto® for Cats is a flea and tick collar that contains imidacloprid and the chemical flumethrin. It kills adult fleas and repels and kills ticks. The collar works for eight months.

Imidacloprid also comes in a variety of Advantage® products for killing fleas, such as shampoos, direct sprays for the cat, carpet spray, yard spray, and a household fogger.

Fipronil is a chemical that kills adult fleas and ticks. It is present in Frontline® products.

Frontline Plus® for Cats contains fipronil to kill adult fleas and ticks and (S)-methoprene to kill flea eggs and larvae. It is a monthly topical formulation.

Frontline Tritak® for Cats contains the fipronil and (S)-methoprene that are present in Frontline Plus, and also has etophenprox. This chemical also kills adult fleas, allowing this product to begin working faster, within fifteen minutes.

Selamectin is present in Revolution® for Cats.

Revolution® for Cats kills adult fleas and flea eggs, ticks, ear mites, and some intestinal parasites. It also prevents heartworm infection. It is a monthly topical medication.

Nitenpyram kills adult fleas very quickly.

Capstar is the product that contains nitenpyram. It is an oral tablet that can be used as often as once a day. It kills fleas very quickly and is useful in keeping them off of an allergic cat while waiting for another product to kick in. It is also good for removing any fleas from your cat quickly when she has been at a kennel or elsewhere. This prevents fleas from entering your home and multiplying.

Dinotefuran is a chemical that kills adult fleas. It is present in Vectra® products.

Vectra® for Cats contains pyriproxifen as well as dinotefuran. This allows it to sterilize adult fleas as well as killing them, thus preventing multiplication in your home. It is a monthly topical product.

Spinetoram is present in Cheristin®.

Cheristin® is a monthly topical that kills adult fleas on cats.

Indoxacarb is the active ingredient in Activyl®.

Activyl® is a monthly topical product that kills adult fleas and sterilizes them.

Treatment of Your Home During Flea Infestation

If your cat develops a flea problem, make sure that you are treating her as well as all other pets in the home with appropriate medications. Your veterinarian can help you choose products based on the needs of your particular household. It may be necessary to treat the environment as well. There are a variety of sprays and other products for use in the home and yard. Be sure you read the labels carefully, as people and pets may need to avoid contact with treated areas for a period of time.

Disclaimer: This website is not intended to replace professional consultation, diagnosis, or treatment by a licensed veterinarian. If you require any veterinary related advice, contact your veterinarian promptly. Information at CatHealth.com is exclusively of a general reference nature. Do not disregard veterinary advice or delay treatment as a result of accessing information at this site. Just Answer is an external service not affiliated with CatHealth.com.